Buggy code:
public class CoreHelper { protected static Category cat = Category . getInstance ( CoreHelper . class ) ; private CoreHelper ( ) { } private static CoreHelper SINGLETON = new CoreHelper ( ) ; public static CoreHelper getHelper ( ) { } public Collection getAllSupertypes ( MClassifier cls ) { } public Collection getSupertypes ( MClassifier cls ) { } public Collection getAssociateEnds ( MClassifier classifier ) { } public Collection getAssociateEndsInh ( MClassifier classifier ) { } public Collection getAttributes ( MClassifier classifier ) { } public Collection getOperations ( MClassifier classifier ) { } public Collection getAttributesInh ( MClassifier classifier ) { } public Collection getOperationsInh ( MClassifier classifier ) { } public MParameter getReturnParameter ( MOperation operation ) { } public Collection getReturnParameters ( MOperation operation ) { } public Collection getSpecifications ( MClassifier cls ) { } public Collection getSubtypes ( MClassifier cls ) { } public void setReturnParameter ( MOperation operation , MParameter newReturnParameter ) { } public MDependency buildSupportDependency ( MModelElement from , MModelElement to ) { } public Collection getAllBehavioralFeatures ( MModelElement element ) { } public Collection getAllBehavioralFeatures ( MClassifier clazz ) { } public Collection getAllBehavioralFeatures ( ) { } public Collection getAllInterfaces ( ) { } public Collection getAllInterfaces ( MNamespace ns ) { } public Collection getAllClasses ( ) { } public Collection getAllClasses ( MNamespace ns ) { } public Collection getRealizedInterfaces ( MClassifier clazz ) { if ( clazz == null ) return new ArrayList ( ) ; Iterator it = clazz . getClientDependencies ( ) . iterator ( ) ; List list = new ArrayList ( ) ; MNamespace model = TheInstance . getProject ( ) . getModel ( ) ; while ( it . hasNext ( ) ) { Object o = it . next ( ) ; if ( o instanceof MAbstraction ) { MAbstraction abstraction = ( ( MAbstraction ) ( o ) ) ; MStereotype stereo = abstraction . getStereotype ( ) ; <START_BUG> if ( ( ( stereo != null ) && ( stereo . getBaseClass ( ) . equals ( "Abstraction" ) ) ) && ( stereo . getName ( ) . equals ( "realize" ) ) ) { <END_BUG> Iterator it2 = abstraction . getSuppliers ( ) . iterator ( ) ; while ( it2 . hasNext ( ) ) { Object o2 = it2 . next ( ) ; if ( o2 instanceof MInterface ) { list . add ( o2 ) ; } } } } } return list ; } public MAbstraction getRealization ( MInterface source , MClassifier clazz ) { } public Collection getExtendedClassifiers ( MGeneralizableElement clazz ) { } public MGeneralization getGeneralization ( MGeneralizableElement child , MGeneralizableElement parent ) { } public Collection getFlows ( MModelElement source , MModelElement target ) { } public Collection getExtendingElements ( MGeneralizableElement clazz ) { } public Collection getExtendingClassifiers ( MClassifier clazz ) { } public Collection getAllComponents ( ) { } public Collection getAllComponents ( MNamespace ns ) { } public Collection getAllDataTypes ( ) { } public Collection getAllDataTypes ( MNamespace ns ) { } public Collection getAllNodes ( ) { } public Collection getAllNodes ( MNamespace ns ) { } public Collection getAssociatedClassifiers ( MClassifier classifier ) { } public Collection getAssociations ( MClassifier from , MClassifier to ) { } public Collection getAllClassifiers ( ) { } public Collection getAllClassifiers ( MNamespace ns ) { } public Collection getAssociations ( MClassifier classifier ) { } public MAssociationEnd getAssociationEnd ( MClassifier type , MAssociation assoc ) { } public Collection getAllContents ( MClassifier clazz ) { } public Collection getAllAttributes ( MClassifier clazz ) { } public MModelElement getSource ( MRelationship relation ) { } public MModelElement getDestination ( MRelationship relation ) { } public Collection getDependencies ( MModelElement supplier , MModelElement client ) { } public Collection getRelationships ( MModelElement source , MModelElement dest ) { } public boolean isValidNamespace ( MModelElement m , MNamespace ns ) { } private boolean isValidNamespace ( MCollaboration collab , MNamespace ns ) { } private boolean isValidNamespace ( MGeneralization gen , MNamespace ns ) { } private boolean isValidNamespace ( MStructuralFeature struc , MNamespace ns ) { } private boolean isValidNamespace ( MAssociation assoc , MNamespace ns ) { } private boolean isValidNamespace ( MGeneralizableElement gen , MNamespace ns ) { } public MNamespace getFirstSharedNamespace ( MNamespace ns1 , MNamespace ns2 ) { } public Collection getAllPossibleNamespaces ( MModelElement m ) { } }

Fix:
if ( ( ( ( ( stereo != null ) && ( ( stereo . getBaseClass ( ) ) != null ) ) && ( ( stereo . getName ( ) ) != null ) ) && ( stereo . getBaseClass ( ) . equals ( "Abstraction" ) ) ) && ( stereo . getName ( ) . equals ( "realize" ) ) ) {